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#1009730 (Received by flhurricane at: 4:59 AM 26.Jul.2020) TCDAT3 Tropical Storm Hanna Discussion Number 14 NWS National Hurricane Center Miami FL AL082020 400 AM CDT Sun Jul 26 2020 Hanna continues to weaken as the center crosses the Rio Grande River from Texas into northeastern Mexico. Satellite imagery shows some warming of the cloud tops near the center, and WSR-88D radar data shows that only about a third of the previous eyewall is still present to the southeast of the center. The storm is generating a vigorous outer convective band over the eastern semicircle. The initial intensity is reduced to 50 kt based mainly on Doppler radar winds of 50-65 kt at about 9000 ft to the northeast of the center, and it is possible that this is generous. The initial motion remains west-southwestward or 250/8 kt. The mid-level ridge over the central United States should continue to steer Hanna west-southwestward until dissipation, and the new NHC forecast track is little changed from the previous forecast. Hanna should rapidly weaken as it moves over northeastern Mexico, with the system expected to weaken to a depression in 12-18 h, if not sooner. The system is expected to dissipate completely over the rugged terrain of Mexico between 36-48 h. The radar signature of the storm has weakened to the point where there will be no more hourly position updates between advisories. Key Messages 1. Tropical storm conditions are expected to persist for several more hours near the center of Hanna, and for a few more hours in the warning area along the coast of Texas and northeastern Mexico. 2. Hanna is expected to produce heavy rains across portions of southern Texas and northeastern Mexico. These rains will result in life-threatening flash flooding and isolated minor to moderate river flooding. 3. Storm surge along the Texas coast should diminish today. FORECAST POSITIONS AND MAX WINDS INIT 26/0900Z 26.3N 98.9W 50 KT 60 MPH...INLAND 12H 26/1800Z 25.8N 99.9W 35 KT 40 MPH...INLAND 24H 27/0600Z 25.1N 101.4W 25 KT 30 MPH...INLAND 36H 27/1800Z 24.5N 102.7W 20 KT 25 MPH...POST-TROP/INLAND 48H 28/0600Z...DISSIPATED $$ Forecaster Beven |